Light-Duty Vehicle Emissions Research and Development

Southwest Research Institute (SwRI) provides comprehensive emissions research and testing expertise to an international clientele. As one of the world's premier emissions research organizations, SwRI maintains excellent facilities and continually advances the state-of-the-art in sample collection, measurement, and data analysis technologies. Serving regulatory agencies and commercial clients, the Institute's world-renowned staff provides expertise in:

• Data analysis and interpretation
• Emissions regulations and procedures
• Product development

SwRI research programs include:

• Automotive catalyst development
• Advanced exhaust aftertreatment technology
• Alternative fuels evaluations
  • Liquefied petroleum gas (LPG)
  • Liquefied natural gas (LNG)
  • Butane blends
  • Compressed natural gas (CNG)
  • Methanol
  • Ethanol
  • MTBE 
• Otto-cycle, diesel, and hybrid electric vehicle propulsion systems
• Experiment design and analysis using advanced statistics
• Conventional fuel and fuel additive evaluations

The Institute's VETS-9200 Horiba modal analysis system measures second-by-second exhaust emissions from light-duty vehicles, before and after the catalytic converter, as well as bagged diluted exhaust emissions. Programmable, variable dilution air flow rate permits accurate measurements of exhaust emissions from ultra-low emissions vehicles (ULEV). Regulated emissions results, temperature, pressure, and voltage data are acquired and analyzed using this flexible, PC-compatible system.

Test Capabilities

SwRI's facilities accommodate a variety of light-duty vehicle exhaust and evaporative emission test equipment including:

• 48-inch single-roll electric chassis dynamometer
• Three Clayton twin-roll hydrokinetic chassis dynamometers
• Horiba modal analysis system
• Beckman raw emissions bench
• Sealed housing for evaporative determinations (SHED)
• Temperature-controlled emissions enclosure (TCEE)
• Separate gasoline and diesel particulate tunnels
• Three analytical benches for dilute exhaust emission samples

SwRI's emissions laboratories are recognized by the Environmental Protection Agency (EPA) and the California Air Resources Board (CARB) and accommodate North American, European, and Asian emissions test procedures, as well as most custom requests.

The Institute monitors diurnal and hot-soak evaporative emissions using a variable-temperature, variable-volume SHED. This facility runs both EPA and CARB temperature profiles for new evaporative emissions test procedures, including the three-day test.

For durability testing, SwRI offers around-the-clock mileage accumulation at speeds up to 100 mph. Twelve mileage accumulation dynamometers (MADS) with 48-inch rolls accommodate light-duty cars and trucks up to 7,000 pounds.

In dedicated facilities, the Institute also evaluates catalytic converter performance and durability. Catalytic converter test capabilities include:

• Catalyst light-off and conversion efficiency Can deformation analysis
• Hot vibration durability testing
• Bench aging

SwRI rapidly and cost-effectively evaluates how fuels, fuel additives, and exhaust aftertreatment systems affect emissions.

Alternative Fuels

SwRI has pioneered the development of techniques to measure emissions from alternatively fueled vehicles, including those operating on CNG, LPG, methanol, and ethanol. With the ability to measure a variety of regulated and unregulated exhaust emissions, scientists can quickly and accurately calculate organic material hydrocarbon equivalent (OMHCE) and non-methane organic gases (NMOG). As a leader in this field, SwRI has developed and published a number of procedures to quantify emissions from alternative fuels, including methods to:

• Calculate emissions and fuel economy for alternate fuels (EPA 460/3-83-009)
• Compute emissions from hydrogen-fueled engines (ASME 92-ICE-15)
• Compute emissions from natural gas and dual-fuel engines (ASME 93-ICE-29)

SwRI has extensive experience evaluating exhaust emissions from alternative-fuel vehicles, including those operating on methanol, ethanol, CNG, LPG, butane, and hydrogen.

SwRI's data reduction programs permit accurate emissions calculations associated with a variety of liquid and gaseous fuels. Comprehensive ASTM fuel and lubricant analyses provide detailed fuel and lubricant assays. Specialized facilities allow SwRI to blend fuel to complex specifications.

Analytical Capabilities

The Institute's advanced chemistry laboratories provide comprehensive chemical analyses of gaseous and particulate samples for all regulated motor vehicle emissions and for numerous unregulated emissions. Emissions most commonly characterized include:

• HC, using flame ionization
• CO and CO₂, using nondispersive infrared techniques
• NO_X, using chemiluminescence
• Methane, according to SAE J1151
• Particulate mass

Using sensitive micro-balances in temperature and humidity-controlled chambers, SwRI measures exhaust particulates from gasoline, diesel, and alternative fuel vehicles.

SwRI developed and patented a direct filter injection chromatography method to measure lubricating oil contribution to exhaust particulates. In addition, the chemistry laboratory has developed or implemented procedures to measure unregulated emissions such as:

• Soluble organic fraction of particulate
• Volatile organic fraction of particulate
• Organic amines
• Ammonia
• Organic sulfides
• Sulfate
• Hydrogen sulfide
• Nickel carbonyl
• Sulfur dioxide
• Total cyanide
• Organics fractionation
• N-nitrosamines
• Phenols
• Tertiary butyl alcohol
• Nitropyrenes
• Benzo a-pyrene
• Selected polynuclear aromatics
• Nitrous oxide
• Alcohols
• Ketones and aldehydes

The Institute specializes in full hydrocarbon speciation according to the most recent Auto/Oil methods, using four gas chromatographs and a high-performance liquid chromatograph. For diesel speciation, SwRI can now characterize compounds up to C₂₂, using a new quadrupole mass spectrometer and automatic thermal desorption system.

Research Support

SwRI supports clients with focused and general research reports, as well as continuing technical support, as needed. Emissions testing activities are supported by specialists in:

• Data acquisition and analysis
• Mechanical and electronic design and fabrication
• Fuel and lubricant analysis
• Instrument design and installation
• Engine diagnostics and modification
• Electron microscopy and X-ray diffraction

SwRI maintains client confidentiality while avoiding any conflict of interest. When appropriate, emissions scientists and engineers present and publish technical papers for professional conferences; more than 50 papers have been presented at SAE and ASME conferences since 1990.

As an example of the Institute's commitment to quality, the Department of Emissions Research is now ISO 9002 certified and ISO/IEC Guide 25 accredited. Instrument calibrations are NIST-traceable. Complete maintenance and calibration records are maintained and may be inspected by clients.

SwRI technicians insert thermocouples into catalyst substrates and install the substrates in custom-fabricated housings. Exhaust system components are modified to accommodate various test pieces. As an applied engineering and physical sciences research and development organization, the Institute is experienced in meeting unusual exhaust system requirements.

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